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HAWK-EYE

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And in the interest of balance for informed commenters, here is Lumagen's take on this from AVS:-

The Pro HDR IM output colors for the Mad Max sand storm explosions are correct based on the pixel data. The explosions are mostly burnt orange with some yellow, not the other way round. The data does not overflow the Pro HDR IM as we initially considered possible. A 1D LUT as used for the ARVE tool cannot process the Tone Mapping correctly since each color is independent and so color balance between R, G, and B will change when they are not supposed to, as in the explosion scene. I initially looked at a 1D LUT approach for IM and immediately tossed it as mathematically incorrect. Took all of 5 minutes to decide this.

NOTE: This is NOT a dig at the ARVE tool. It uses the hardware available in the projector (a 1D LUT) and does a pretty good job with what is available.

The term "illegal colors" is too strong. Rather colors should be "Protected for RGB" in the editing stage. This has been standard practice for many years. Not doing so means the colors change as one primary clips first due to how the color space conversion calculation works. Having YCbCr values that cause clipping in RGB is a big issue, but it is not an issue in the Mad Max sand storm scene (at least not for the Pro IM).

Saying one wants the explosions to look yellow when they are mostly burnt orange is like saying I want my grass to be pink. Maybe so, but no good way to make an exception in the math that does not also screw up other colors too. And you would of course be seeing the wrong color for grass. Does not make sense. Reminds me of people liking their whites to be blue because they got used to TVs in "torch mode."

Interesting side note: I checked the color verses temperature of a propane explosion. Going from hot to hotter you have yellow, then orange, and then red. So, the central part of the explosion being hotter should be burnt orange or orange, with the fingers of the explosion cooling to orange and yellow. In my opinion this is how it looks with the Radiance Pro HDR IM, and this matches the data on the disc.

I would be interested in seeing the sand storm scene on the Pulsar monitor it was edited on to confirm all this, but I am convinced it would confirm the Pro IM rendition of color.

There, I have created my own sandstorm.



After more deliberations.

Lumargen Pro work in progress.......

fyaKL6c.jpg


Lumagen:-
"We will be changing the HDR IM parameter defaults in the next release. These changes will affect only the defaults when the parameters are reset (in the HDR IM parameters menu, or a factory reset, plus a Save). We need to thank Kris Deering for his work testing the various permutations of Display Max Light, Tran and Shape to discover the optimal settings."
 
After more deliberations.

Lumargen Pro work in progress.......

fyaKL6c.jpg


Lumagen:-
"We will be changing the HDR IM parameter defaults in the next release. These changes will affect only the defaults when the parameters are reset (in the HDR IM parameters menu, or a factory reset, plus a Save). We need to thank Kris Deering for his work testing the various permutations of Display Max Light, Tran and Shape to discover the optimal settings."

I'm struggling to understand your agenda here?

Tone-mapping is a software implementation, based on mathematical algorithms. Lumagen are providing a set of tools where you can adjust certain settings for different scenarios, because essentially HDR is a mess. Unlike many vendors they allow and respond to their customer feedback, and release updates and improvements accordingly. The aspect above is a completely different context to the scenario you are replying to. I don't understand all of the technical details but Mad Max explosions is essentially a bad HDR/Colour mastering in the movie presentation. The author of MadVR has supported this.

Completely separate to this a respected AVS forum member has been doing lots of testing on Lumagen's HDR tone-mapping solution, in different scenarios, and has suggested some optimisations, which Lumagen agree with, and so are working on releasing an improved version.

The alternative is to rely on tone-mapping done within the displays themselves, which based on vendor track-records would be a one-and-done implementation, never to be touched again, despite any known flaws or shortfalls.
 
I have no agenda just pointing out the limitations like others do on this forum.
Mad Max Fury Road is 1 of many that will clip if using Lumagens Pro solution.

A quick search finds the below films exceed Lumagens Pro Intensity Mapping - Max Content Light Level (MaxCLL) threshold so scenes will clip (read Gordons post below) like the above sample pic, released almost a year ago for HDR content Intensity Mapping and only now getting an update.......soon............

Confirmed list
MaxCLL - Max Content Light Level

10000 Inferno
4897 The Da Vinci Code
10000 Ghostbusters 2016
9633 Ghostbusters
9887 Ghostbusters II
6414 Life
3940 Hunger Games MockingJay Part 2
6968 The Magnificent Seven
8985 Crouching Tiger Hidden Dragon
9919 Mad Max Fury Road
4000 Man of Steel
3955 Men In Black
10000 Men In Black II
10000 Fifth Element
4491 Baby Driver
10000 Close Encounters of the Third Kind
10000 Bridge on the River Kwai
3995 Starship Troopers
9978 Starship Troopers 2
8154 Chappie
4000 Batman Vs Superman
 
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I have no agenda just pointing out the limitations like others do on this forum.
Mad Max Fury Road is 1 of many that will clip if using Lumagens Pro solution.

A quick search finds the below films exceed Lumagens Pro Intensity Mapping - Max Content Light Level (MaxCLL) threshold so scenes will clip like the above sample pic, released almost a year ago for HDR content Intensity Mapping and only now getting an update.......soon............

Inferno
The Da Vinci Code
Ghostbusters 2016
Ghostbusters
Ghostbusters II
Life
The Magnificent Seven
Crouching Tiger Hidden Dragon
Mad Max Fury Road
Starship Troopers
Chappie
Kong Skull Island
Interstella
Underworld
Underworld Blood Wars
Dunkirk
Blade Runner 2049
Wouldn't this be better off in a Lumagen thread?
 
I have no agenda just pointing out the limitations like others do on this forum.
Mad Max Fury Road is 1 of many that will clip if using Lumagens Pro solution.

A quick search finds the below films exceed Lumagens Pro Intensity Mapping - Max Content Light Level (MaxCLL) threshold so scenes will clip like the above sample pic, released almost a year ago for HDR content Intensity Mapping and only now getting an update.......soon............

Inferno
The Da Vinci Code
Ghostbusters 2016
Ghostbusters
Ghostbusters II
Life
The Magnificent Seven
Crouching Tiger Hidden Dragon
Mad Max Fury Road
Starship Troopers
Chappie
Kong Skull Island
Interstella
Underworld
Underworld Blood Wars
Dunkirk
Blade Runner 2049

You clearly do have an agenda. I’d suggest posting this on the lumagen thread, but from personal experience having watched Kong, interstellar and blade runner since installing the lumagen, the picture is far superior to any previous sitting. I’m sure @Apollo who has seen my combo and has absolutely zero bias towards the lumagen, but clearly knows his stuff will give his opinion if asked.....
 
You clearly do have an agenda. I’d suggest posting this on the lumagen thread, but from personal experience having watched Kong, interstellar and blade runner since installing the lumagen, the picture is far superior to any previous sitting. I’m sure @Apollo who has seen my combo and has absolutely zero bias towards the lumagen, but clearly knows his stuff will give his opinion if asked.....

Plus, for the users who want ultimate quality for each session, you can adjust the tone mapping parameters, to optimise for any film known to be mastered stupidly (probably my bad here, but WTF are they mastering to a level that consumer displays cannot achieve, on consumer discs?). And hopefully in the future Lumagen will be able to detect and adjust dynamically. Where do you have such options on any other implementation of tone-mapping, except for maybe MadVr?
 
I see Jim has just posted at AVS but i'll put this here anyway for those who may stumble across this in the future.

Some clarification and i am sorry this is bunging up a thread about projectors but i think it needs to be cleared up.

Lumagens IM was introduced 20th may 2017 11 months ago….
10 days later new update to deal with 1000 and 4000 nit master content using different parameters
end of June 17 further improvements to IM
end of August 17further improvements to IM including auto correction for raised black level mastered discs
end of october added programmable crossover point for HDR IM
march 2018 added HLG support

Also, Hawk-Eye’s comprehension of how Lumagen IM works its actually wrong and he has posted incorrect information. There is no clipping in the Lumagen HDR IM algorithm.

the “update” that i think HAWK EYE is talking about is a change to default settings based on customer feedback and testing. It is not a change to the actual Algorithm but, as you can see, when possible, improvements are made and customer feedback is always considered so, to that end here is some further information from Lumagen themselves.

From Jim Peterson, Lumagen
“The poster is incorrect. The scenes are NOT clipping in the Pro. The color rendered by the Radiance Pro is the color on the disc. In fact the Pro looks as it does because it does NOT clip the colors and other Tone Mapping apparently is clipping or at least desaturating the colors.

The Radiance Pro's response is mathematically accurate. However, some experienced people are suggesting the Pro desaturate the colors for these extreme bright saturated colors. So, we are looking at desaturating the brighter colors some since some people seem to prefer this even though this will actually make the color less accurate as compared to what is on the disc.

I would also like to note these scenes are one, or at most a few, frames. For example the Mad Max Fury Road Lightening scene (28:53), the bright lightning involved in this discussion is a single frame (plus one or two frames with significantly reduced brightness not affected by this discussion). You would have to pause on the scene to notice the differences if we choose to desaturate the color. The flames on the car are shown for a few flames but again the Pro is showing the colors as they are on the disc.

It is also commonly discussed that early HDR titles like Mad Max Fury Road actually have inappropriate choices for these brightly saturated colors. And that as the colorists have more experience editing HDR the colors on the disc will be desaturated in editing so that they do not have to be desaturated by Tone Mapping. This is subject to debate, but the big issue with having over saturated color on the disc is that if Tone Mapping is changed to render the oversaturated colors as some people want, rather than what is on the disc, when a colorist truly wants to exploit the 2020 color Gamut and produce highly saturated colors it will not be possible because the Tone Mapping algorithms will desaturate the colors. So this discussion is really about do we change the Tone Mapping algorithm to NOT be accurate for these early titles at the expense of future titles that truly need the highly saturated colors?

We will be looking at ways to make the Radiance Pro Tone Mapping even better and we may well choose to put in some desaturation. However, it is my strongly held opinion that Tone Mapping should accurately portray the color on the disc/video-stream (as I believe the Pro does) and that it is up to the colorist to desaturate colors if they would otherwise be over saturated from what a viewer would like to see. The colorist has knowledge of what he/she wants to see, we have only the data on the disc and math."
 
Plus, for the users who want ultimate quality for each session, you can adjust the tone mapping parameters, to optimise for any film known to be mastered stupidly (probably my bad here, but what the fudge are they mastering to a level that consumer displays cannot achieve, on consumer discs?). And hopefully in the future Lumagen will be able to detect and adjust dynamically. Where do you have such options on any other implementation of tone-mapping, except for maybe MadVr?

Panasonics new player.
http://www.*/news/panasonic-ub9000-201802234550.htm

Edit:
So the Lumagen Pro oversaturates when tone mapping and is not clipping but still losing highlight details.
If owners are posting pics like above then something needs to be addressed.
 
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Panasonics new player.
http://www.*/news/panasonic-ub9000-201802234550.htm

Edit:
So the Lumagen Pro oversaturates when tone mapping and is not clipping but still losing highlight details.
If owners are posting pics like above then something needs to be addressed.
The UB9000 is not expected until the tail-end of this year, so a pointless comparison.

Suggest you read @Gordon @ Convergent AV post above, unless you are just wilfully ignoring or misunderstanding when explanations are given.
 
The UB9000 is not expected until the tail-end of this year, so a pointless comparison.

Suggest you read @Gordon @ Convergent AV post above, unless you are just wilfully ignoring or misunderstanding when explanations are given.

So this owner should stop reporting his findings?
Improving Madvr HDR to SDR mapping for projector - Page 18 - AVS Forum | Home Theater Discussions And Reviews

Has it occurred to owners here to corroborate his finding?

Some UK Blu-rays are mastered different to US ones so check if doing like for like.
 
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So this owner should stop reporting his findings?
Improving Madvr HDR to SDR mapping for projector - Page 18 - AVS Forum | Home Theater Discussions And Reviews

Has it occurred to owners here to corroborate his finding?

Some UK Blu-rays are mastered different to US ones so check if doing like for like.
Do you own one or have you made yourself an unofficial spokesperson for those who are not happy and what’s all this talk of the Lumagen doing in a JVC Projector thread?
 

No, they're posting in a constructive and useful way which is likely to improve HDR mapping and knowledge for all, in relevant threads. Maybe there is something in that... ;)

Reading the threads over at AVS it is pretty clear that Jim from Lumagen is very open minded about best approaches in difficult situations. In the Mad Max video for example there are colours that even the colorist couldn't have known what they should look like because they're above the max spec of the Pulsar monitor it was mastered on!
 
Highlight detail loss (link owner reports) is not the same as oversaturated? Or is it?


Madshi wrote
"1) Lumagen's IM does not desaturate at all. It's the same approach which madVR uses if you select the option "100% luminance reduction, 0% saturation reduction". IMHO that's not a good choice, to be honest. As you can see, it produces highlight detail loss in some scenes. Ok, these scenes are extreme cases, but they do occur."
 
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Do you own one or have you made yourself an unofficial spokesperson for those who are not happy and what’s all this talk of the Lumagen doing in a JVC Projector thread?

No but I have seen the result in madVR `above settings` and as there are quite a few owners in this thread looking.
 
Have you actually seen a Lumagen Pro in action? If not, I suggest you stop spouting about stuff that you don’t know about.

You obviously have an agenda here, I just hope that people reading this aren’t put off looking at a Lumagen if they are in the market for such a device, based on your comments.

I think you’ll struggle to find a Lumagen pro owner that is now completely satisfied with its performance, and I would guess that every single one of them has seen a drastic improvement in picture quality since adding it.
 
No but I have seen the result in madVR `above settings` and as there are quite a few owners in this thread looking.
Yet ironically the thread you are referring and linking to is about MadVR and it's more discerning users feeding back to the author their findings on MadVR's deficiencies in HDR-tone-mapping, and asking him to improve it. The problem is the main deficiencies are coming from badly authored HDR implementations on the Disc. At one point a more vocal poster raised stakes by essentially saying "I bet Lumagen isn't as bad as this?" which drew comparisons, but only in efforts to compare techniques by way of improving and maybe working around these bad examples. It's pretty clear from just a brief look that the MadVR author and Jim of Lumagen pretty much agree on a lot of stuff, and clearly have a professional and mutually respectful relationship, and both have clearly demonstrable track-records of listening to their customers and providing ongoing improvements and services. I think the other issue at play here is that colouring (and HDR) seems to have a blurred line between science and art, and in this respect, at a fine detail level is subject to opinions and interpretation.
 
You clearly do have an agenda. I’d suggest posting this on the lumagen thread, but from personal experience having watched Kong, interstellar and blade runner since installing the lumagen, the picture is far superior to any previous sitting. I’m sure @Apollo who has seen my combo and has absolutely zero bias towards the lumagen, but clearly knows his stuff will give his opinion if asked.....

You rang m'lord :)

Just to be clear I have no dog in this fight and despite the kind words above I am definitely running to catch up with this HDR stuff. Never owned a JVC or Lumagen, a neutral observer escaped from the Sony SXRD 4k leper colony!

My take on all this, is that HDR from the grading to the electronics manufactures end is problematic. By which I mean it appears to generally be a bit of a mess.

I personally am glad that there is the knowledge and will within the enthusiast and specialist software/hardware suppliers community to expand the understanding of the issues and find solutions.

If I am understanding this right, the basic beef here is with how the display of a handful of frames (or a single frame) in a couple of earlier UHD titles is handled by the current version(s) of software which are themselves a work in progress. The discs themselves contain possibly rogue pixel data above the display max luminance which the colourist may not have even seen on the mastering monitor (only visible as a spike on the waveform monitor?). Is this really the most significant problem to resolve with consumer HDR?

I've had a good few hours viewing a X7900 plus Lumagen calibrated by Gordon and can attest that the other few hundred thousand frames of Fury Road and other titles seen were displayed flawlessly. Far better than I've seen anywhere else previously, particularly in regards to colour whether on a projector or TV for that matter.

Unfortunately I didn't see the offending frame as it went by too quickly :rotfl:
 
Now go and watch Ghostbusters 2016 00:41:48......
 
In a subsequent discussion by Madshi over at AVS where he is quite certain that the explosions in Mad Max were probably orange on the Pulsar mastering monitors used by the colorists (and so the Lumagen approach was probably the correct one), or why the yellow shift seen when using ARVE curves is actually the result of an error in the approach that the built-in HDR mapping in the JVC works (ie it doesn't maintain hue as you go up the luminance curve).

Edit: for anyone interested in that discussion see here:
Improving Madvr HDR to SDR mapping for projector - Page 15 - AVS Forum | Home Theater Discussions And Reviews
 
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What Lumagen needs is what MadVR has a Dynamic Mode that will subdue the Luminance/oversaturation and balance out the highlights as what I have seen mimicking how the Lumagen handles the conversion the cyan/blue bright scenes look a mess..

You owners should get more pro active.
 
Ghostbusters 2016 41:38 ish ICtCp

LUM 100 SAT 0 (Lumagen)
voZJcOV.jpg


DYNAMIC
Diuvgjk.jpg
 
Administrator's Comment: I have removed or edited a few recent posts. I haven't the patience to go back further than I have. I will not tolerate pointles bickering. If I see more, there will be consequences that extend beyond post removal.

If you can't make your point without cross-referring to and then criticising another member, then keep it to yourself.

Now post on the subject and not about each other. Or don't post.
 
Updated above list of films that Lumagens implemented Intensity Mapping will manifest the above.
 
Ghostbusters 2016 41:38 ish ICtCp

LUM 100 SAT 0 (Lumagen)
voZJcOV.jpg


DYNAMIC
Diuvgjk.jpg


What are we looking at here? Which one is the way the director intended?
 
Would be helpfull with some Lumagen Pro user in this thread who actually knows how to operate a Lumagen, its always messy when 2nd hand information gets tossed around.
Lumagen is one of the few companies left who do a lot to add features, and even its not always a perfect hit, they keep on trying.
 
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